In the past, many closures have been developed for enclosing an opening in a container. For the purposes of this invention, the term "container" includes, but is not limited to, flexible bags, boxes, cartons, or any like receptacle having a defined opening providing access to the interior of the container. For instance, containers have been provided with a coating of an adhesive that adheres one portion of the container to another portion of the container to enclose the opening therein.
Adhesives that permanently adhere the container portions together require that the container be damaged in order to open the container. Further, the container may not be reclosed once opened. Closures having pressure sensitive adhesives have also been utilized that enable the container to be opened without damaging the container and also enable the container to be reclosed once opened. Although the pressure sensitive adhesive closures are useful, they exhibit certain undesirable characteristics. For instance, debris or other impediments may become adhered to an exposed surface of the pressure sensitive adhesive and render the adhesive ineffective. This is particularly troublesome in that the contents of a container may inadvertently adhere to the exposed pressure sensitive adhesive surface while being placed within or dispensed from the container. Pressure sensitive adhesives may also lose adhesive strength over long periods of time.
Containers have also been constructed in the past having fasteners or closure members that are mechanically interlocked together. For instance, bags have been constructed of flexible polymeric film and incorporating a Ziploc.TM. interlocking closure available from Dow Chemical Co. of Midland, Mich. Mechanical fasteners such as Ziploc.TM., although reusable, are difficult to align when closing. Further, it is difficult to produce thin mechanical interlocking closures.